A suffocating tale of isolation and warped emotional attachment, the new movie “Labor Day” is only a few steps away from an excellent psychological chiller. If they’d changed the ending and made the soundtrack just a little more menacing, they might have ended up with something that would have had people waking up in a cold sweat for years.

Unfortunately, I’m almost positive it’s supposed to be a romance.

A baffling misstep from the normally reliable director Jason Reitman, “Labor Day” is an uncomfortable, uneasy mess of a movie that leaves you wondering how anyone thought making it could possibly be a good idea.

The script broadcasts its ambitions to be the next “Bridges of Madison County” loudly enough to make audiences’ ears bleed, an ambition that is constantly thwarted by the film’s menacing undertone and unfortunate Oedipal subtext. All of the narrative cues tell you that what’s happening is supposed to be touching and romantic, while at the same time your subconscious is pretty sure you should be screaming.

The plot, as outlined for us in painfully heavy-handed narration, starts with a young man being raised by his clearly severely depressed mother Adele. He’s clearly devoted to her, rejecting his father’s offers to come stay with him and giving his mother “husband for a day” coupons. She teaches him dancing and has entirely inappropriate discussions with him about how good sex feels.

As Adele, Kate Winslet offers up a finely detailed, surprisingly terrifying portrait of a woman sunk so deeply into depression that she’s desperate to feel anything at all. Winslet’s face is a study of a woman about to break at any moment, and the audience is left constantly on edge wondering whether she’ll burst into tears or go for a kitchen knife.

The sense of warped emotion only increases with the addition of an escaped convict into their lives. The movie makes it clear that Frank was supposedly wrongly imprisoned, but Brolin gives the character such flat, quiet menace that it’s hard to see him as a victim. Everything he says sounds threatening, even when he’s spouting cross-stitchable nonsense about baking pies. When he and Adele fall into bed together, it seems less like an epic romance and more like the back story for a murder-suicide.

And that’s not even mentioning young Henry, played by Gattlin Griffith as if Reitman ordered him not to make facial expressions of any kind. He stares at his mother and Frank like he’s jealous, and the voice-over while he’s listening to their lovemaking was funny in the most horrible way possible. I laughed – I’m a terrible human being – but I don’t think Reitman meant it as a joke.

While I was watching the movie, though, I had hope that he might have. Maybe they advertised it wrong, I thought, and this is in fact a brilliant examination of the inner darkness of these kind of fantasies. Surely no one can be this creepy by accident, right?

But then the ending came, chock full of the ridiculously contrived romantic nonsense designed to inspire tears in the audience, and my hopes were dashed. “Labor Day,” sadly, is definitely not a horror movie. You’ll just wish it was.